package main

import "fmt"

func main() {
	sum := 0
	for i := 0; i < 10; i++ {//MARK 注意 没括号
		sum += i
	}
	fmt.Println(sum)

	sum = 1
	for sum < 1000 {//MARK 没 while
		sum += sum
	}
	fmt.Println(sum)

	for {//MARK 无限循环
		break
	}
}
